For the third time this year, the FDA has approved a new antibiotic to treat acute bacterial skin and skin structure infections.

For the third time this year, the FDA has approved a new antibiotic to treat acute bacterial skin and skin structure infections.

Oritavancin (Orbactiv), a lipoglycopeptide given as a single 3-hour infusion, was noninferior to 7 to 10 days of twice-daily intravenous vancomycin in two large clinical trials, the FDA said in a statement.

All three drugs were approved after being designated Qualified Infectious Disease Products under the Generating Antibiotic Incentives Now title of the FDA Safety and Innovation Act.

The designation allows for a priority review, as well as a longer period of marketing exclusivity once a drug is approved.

"The approval of several new antibacterial drugs this year demonstrates that we are making progress in increasing the availability of treatment options for patients and physicians," said Edward Cox, MD, director of the Office of Antimicrobial Products in the FDA's Center for Drug Evaluation and Research.

But "more work is needed in this area," Cox said in a statement.

Skin and skin structure infections are common and have a substantial impact on healthcare systems, MedPage Today has been told, and getting FDA approval for those infections appears to be easier than for other indications.

While clinicians are comfortable with vancomycin -- a standard drug for decades -- there is great interest in finding new drugs with different dosing characteristics to supplement or replace it.

Vancomycin has some important drawbacks, including the need for an indwelling catheter for several days, which in many cases also means patients must be admitted to hospital for the duration of the treatment.

Oritavancin is approved to treat infections caused by susceptible bacteria, including methicillin-susceptible and -resistant Staphylococcus aureus, various Streptococcus species, and Enterococcus faecalis.

The approval was based on results of two randomized clinical trials, dubbed SOLO-I and SOLO-II, that included a total of 1,987 adults with acute bacterial skin and skin structure infections.

Patients were randomly assigned to either 1,200 milligrams of oritavancin in a single infusion or vancomycin twice a day at either a fixed dose of one gram or 15 milligrams per kilogram of body weight.

The novel drug was noninferior to vancomycin on an FDA-established endpoint: clinical improvement at 72 hours, defined as cessation of spreading, absence of fever, and no use of rescue antibiotics.

The most common side effects identified in the clinical trials were headache, nausea, vomiting, the formation of skin and soft tissue abscesses on arms and legs, and diarrhea, the FDA said in a release.

The label also includes a warning regarding interference with coagulation tests and interaction with warfarin.